HelioFill on one test map per held-out rotation (top to bottom: CR 2115, 2128, 2141, and 2151; 2011 October 14 04:00, 2012 September 18 23:00, 2013 September 04 18:00, and 2014 June 04 03:00 UT), each the median of its rotation in HelioFill’s correlation over the unobserved sector (ρ_S = 0.569, 0.510, 0.544, and 0.604; PSNR_S14.81, 14.71, 14.53, and 16.50 dB). Left: two-view input (black: unobserved sector); middle: HelioFill; right: three-view target. Cyan: edge of S. All panels share one color scale. Figures 4 and 5 zoom in on the sector of these maps. The small-scale texture inside the estimated sector is generated by the refinement stage, which is not observed (Appendix C).